A 29-year-old man has sued the manufacturers of a sexual enhancement supplement, claiming it caused his penis to fracture in a horrifying incident at Houston motel last year.

But though Adrian Carter of Texas blames the supplement, three urologists told ABCNews.com com that penile fractures are most often the result of rough sex.

Adrian Carter of Texas said he purchased VirilisPro in the "early morning hours" at a Chevron gas station en route to the Scottish Inn, where he had sex with his "paramour," according to the lawsuit.

Later, during intercourse, he had "significant pain and observed a large quantity of blood squirting out of his penis onto the sheets, walls and mirror," according to the lawsuit filed Aug. 27 in the district court of Harris County, Texas.

Emergency room doctors had to "deglove" Carter's penis in order to repair it, rendering him unable to have sex or future children, Carter claimed.

The lawsuit said VirilisPro was "defective and unreasonably dangerous for use by consumers."

"It was pretty horrific to view the pictures," Carter's lawyer, Melissa Moore, told ABCNews.com. "I know it sounds unusual. ... He was young and healthy and on no other meds at the time he took the supplement."

Named in the lawsuit were the drug manufacturer, Haute Health Limited Liability Company, Carney & Carney Financial Services, individuals Michael Heilig and Michael and Tyra Carney, and Solid Rock Worship Company, all located in New Jersey.

On its website, the company says VirilisPro is "made with only natural ingredients to prevent harmful side effects."

But urologists said penile fractures usually are caused by traumatic sexual intercourse.

And they are fairly common, according to Dr. Chad Ritenour, associate professor of urology at Emory University School of Medicine in Atlanta. He sees a case -- called "eggplant penis" -- at least once a month.

"I never heard of anyone being put at a higher risk for fracture because of a prescription or an herbal drug," said Carney. "With a fracture, you typically get swelling and the penis looks like an eggplant -- purple and swollen. But blood coming out on the walls, that sounds really dramatic.

"The typical story is that someone is having intercourse and, in the course of an erection, they miss an opening and hit a pelvic bone in their partner," he said. "In the classic case, you hear a 'pop' and feel something immediately."

Carter said he was taken to a local emergency room, where the doctor diagnosed him with "gross hematuria" -- blood in his urine -- as well as penile fracture and a urethral injury, according to the lawsuit.

There, after "initial exploratory surgery," doctors allegedly "degloved," or removed the skin from the penis, and repaired his urethra, which had "separated completely."

Carter was released from the hospital after a few days, but a catheter remained in place for three days, according to the lawsuit.

"Doctors again warned him that he may never have an erection or be able to father children and his ureters [sic] may close, resulting in permanent inability to urinate naturally," according to court papers.

Dr. Jeanne O'Brien, an associate professor of urology and male fertility, said penile fractures can traumatize the urethra.

"They often happen together and it is routine to clear the urethra in cases of penile fracture," she wrote in an email to ABCNews.com. "Surgical repair is the only option in these cases."

According to its website, VirilisPro is a supplement to improve sexual performance that "works to give you a harder erection for natural male enlargement and a more intense orgasm. It also helps lower your recovery time and increase sexual stamina for total sexual enhancement."

Its online advertising says that the product is "made with only natural ingredients to prevent harmful side effects." Its ingredients are listed as a 450 mg "proprietary blend" of epimedium, tribulus terrestris, panax ginseng, rhodiola rosea, lycium chinese and yohimbe extract.

Male consumers are instructed to take it 30 minutes before intercourse and only use one pill in a 36-hour period. The ad warns the user to "always check with a healthcare professional" first.

The Food and Drug Administration does not regulate dietary supplements in the same ways they do food and drugs. The dietary ingredient manufacturer is responsible for ensuring that it is safe before marketing it. The FDA can take action against any unsafe supplement, according to their guidelines.

Alleging that supplements caused penile fracture is "the most absurd thing I have heard of in my life," according to Dr. Jeff Carney, chief of urology at Grady Memorial Hospital and a trauma specialist.

Some of Carter's symptoms as described in the court papers ring true -- pain and swelling, according to Carney, but other details are "overly dramatic," he said.

Degloving would never have been done in an emergency room, but by a skilled surgeon, he said. If the urinary channel is also affected by the fracture, the injury can be bloody, but "blood squirting out helter skelter" is not possible, "I can guarantee you," he said.

"When a man breaks his penis it can be very scary," said Carney. "I believe he took this story and spiced it up."

Carney said that he has heard "everything under the sun" when men arrive in the emergency room with a fractured penis. "The most common one told is they walked into an ironing board."

"I suppose it's possible you could get up in the middle of the night with a hard erection and a walk into a wall and break your penis," he said.

Urologist Ritenour agreed.

"You never know if you are getting the real story," he said. "People are embarrassed. The real point of this story is that this is a medical emergency and you really need to come and be seen so it can be handled surgically and fixed."